Big end construction for motors



C. L. LAWRANCE. BIG ENO CONSTRUCTION FOR MOTORS. APPLICATlorLFILED MAY7,1920.

1,404,617, Patented .1an.24,1922.

Zilvj l Z711' lzalflfJ'LLaI/uwlme 5J Hiring-12,

C. I.. LAV/RANCE.,

BIG END CONSTRUCTION FOR IVIOTORSA APPLICATION FILED MAY 7. I920.

l ,404, 6 1 7. Patented Jan. 24, 1922,

2 SHEETS-SHEET 2.

` UNITED STATESv PATENT OFFICE.

CHARLES L. LAWRANCE, OF BAY SHORE, LONG ISLAND, NEW YORK, ASSIGNOR TO LAWRANCE AERO ENGINE CORPORATION, A

CORPORATION OF NEW YORK.

BIG END CONSTRUCTION FOR MOTORS.

Specification of Letters Patent.

Patented Jan. 24, 1922.

To all whom it may concern.' i

Be it known that I, CHARLES L. Law- RANcE, a. citizen of the United States, residing at Bay Shore, Long Island, county'of Suffolk, State of New York, have invented certain new and useful Improvements in Big End Constructions for Motors, of which the following is a specification.

The subject matter involved in the present case is a big end construction for motors and particularly those motors of a radial type in which a plurality of connecting rods are assembled on a single crank pin. In motors of this type a. popular form of construction is one in which a bearing foot isv .provided on lthe end of each connecting rod,`

these feet being guided vin an annular way on a bearing encircling the' crank pin.- Such structures have many points of advantage but have developed certain difficulties among which may be. noted those resulting from the'tendency of the foot to skew' the raceway. Y

It is therefore the object of the present in-' vention to so improve the interrelated parts of such a. big end construction as to afford a maximum bearing surface for the foot and at the same time to provide preventative means for the avoidance of any skewing tendency of the rod foot.

As illustrative of the present invention there is shown a big end construction in detailed design as being one which has been l found well adapted for practical use. The

specific design is not however to be construed as indicatingany limitation of the invention to detail, but as being illustrative and explanatory of the invention. itself.

Throughout the specificationand drawings like reference characters are correspondingly employed, and in the drawings:

Fig'. Iis a vertical section through thev big end assembly.

Fig. II an elevation of the same.

Fig. III an endviewof a connecting rod.

Fig. IV a side view of the same.

Fig. V `an end viewv of therod the foot, and Fig. VI a section on the line VI-VI of Eig. V.

In the construction shown, there is provided on the crank pin 1 a pair of'ball bearingsv 2 assembled Awithin the ring 3 showing which acts as a guideway for the feet of a plurality of connecting rods 4.* The foot of each of the connecting rods as will be more clearly seen by reference to Figs. III, IV and consists of a slightly arched diagonally disposed segment 5 on the end of the connecting rod. This portion 5 constitutes the foot proper but is provided on each side with lateral flanges 6. It will be understood that where a large number of cylinders are used the rod foot must be relatively small. It is of t-he utmost importance however that the are of bearing of the foot be as large as possible. For this reason I form eachk rod foot at an angle to the axis of the bearing. This gives a maximum arc and also staggers the flanges 6 and decreases the tendency to skew. By reference to Fig. V therefore it will be seen that the foot 5 is cut at each end on a diagonal or oblique `line instead of straight across or at iight angles. .The two ends of the foot are cut on the same angle sothat the foot forms in plan a parallelogram flanged as at 6 on each narrow sidewhich brings the fianges at different circumferential portions.

The flanged foot thus described has its main or direct bearing on a sleeve or bearing 8 which is assembled within the two parts 9 and 10 of the guideway. In the structure shown, this `guideway is divided in a plane at right angles transversely through its axis which permits the ready assembly, the two parts being fastened by the screws 11 passing through the flanges 12 and 13, formed within the ring. The width of the bearing 8 just referred to is somewhat less, than the internal breadth of the ring so that on each side of the bearing 8 betweenA it and the inner side walls of the ring members 9 and 10 there is left a narrow groove or channel. In this channel the fianges 6 are guided. By reason of the shape of the foot 5 these flanges have a somewhat staggered relation which gives a greater distribution of any strain resulting from. tendencies of the conneetinr rod to twist. In some cases it has been fun advisable to slightly modify the shape of the foot 5 locating it more or less unsymmetrically with reference to the connecting rod, but it will be understood that any such modification in the distribution of flanges are within the spirit of the invention.

In combination with the bearing shown, the Acrank pin 1 preferably has an integral part with an arm 14 on one portion of the shaft 15. The other crank arm 16 on the shaft portion 17 is preferably provided With an opening 18 which is tapered to receive the tapered end 11 of the crank pin 1. The end of the crank pin is drawn tightA in this taper by a threaded holding member 19- tapped into the open end of the pin 1 which is preferably formed hollow. The member 19 has an enlarged head 19l to afford suitable bearing on the arm 14. In addition to the modifications ossible in the shape of the foot as hereinbe ore mentioned, various other modifications may obviously be resorted to in other parts of the structure and combination thereof, allthese are deemed to be Within the purview of this invention if within the limits of the appended claims.

What I therefore claim and desire to secure by Letters Patent is:

1. In ,a crank pin assembly, a crank pin bearing sleeve, a peripheral guideway about` said sleeve and having an inward groove, a'

plurality of footed connectin rods assembled on said Way, each rod oot vhaving a lateral toe flange disposed in said groove and guided thereby.

2. In a big end construction of the class described, a connecting rod foot comprising a central bearing portion, and a depending lateral. flange on each side of said foot.

3. In a crank pin assembly a crank pin bearing sleeve, a peripheral guideway about said sleeve and having an inward grooveat each side thereof, a plurality of footed connecting rods assembled en said Way, each rod foot having lateral toe flanges disposed in said groove and guided thereby.

4. In a big end construction of the class described, a connecting rod foot comprising an arched central bearing portion having its ends disposed at an angle to the axis of rotation, anda pair of depending lateral flanges on each side of said foot.

5. In a crank pin assembly a crank pin bearing sleeve, a peripheral guidevvay about .said sleeve and having an inward groove at tral portion disposedk at an angle to the axis of rotation of the crank pin.

7 A connecting rod foot for a crank pin, comprising an arched central bearing portion, and depending flanges at each end of said central portion disposed parallel to each other and at an angle to the axis of rotation' of the crankpin. In testimony whereof I affix iny signature in presenceyof two witnesses.

CHARLES L. LAWRANCE.

Iitnesses -JOSEPH IVERTZHEISER, HARRY E. RADAGK. 

